According to Intuit, Error Code -6189, -1005 “QuickBooks was unable to open the company file” can occur when attempting to open a QuickBooks company file (.qbw) created in a previous version of QuickBooks (e. g., 2008 or earlier) in QuickBooks 2009. The Intuit article linked below also includes the contradictory explanation that the error is caused by attempting to open a QuickBooks 2009 company file (.qbw) in a previous version of QuickBooks – something that is not allowed.
This error text is also displayed:
QuickBooks was unable to open the company file <filename> on your computer. A possible reason for this may be that you don't have read/write permission for the files under the folder where the company file is saved. Obtain this permission and then try opening the file
At this time, the error is unresolved. Intuit is investigating a resolution which may be included in a future QuickBooks release.
For more information on resolving Error Code -6189, -1005, consult this Intuit knowledge base article.